EXHIBIT 21

QUIXOTE CORPORATION & SUBSIDIARIES  SUBSIDIARIES OF THE COMPANY  as of June 30, 2004

|QUIXOTE CORPORATION (PARENT)        |                                 | Jurisdiction
Under Which
Organized                      
|----------------------------------- | ------------------------------- | --------------------------------------------------------
|Quixote Transportation Safety, Inc. |                                 | Delaware                                                
|                                    | TranSafe Corporation            |                                                         
|                                    |                                 | Nu-Metrics, Inc.                                        
|                                    |                                 | Highway Information Systems, Inc.                       
|                                    |                                 |                                                         
|                                    | Surface Systems, Inc.           |                                                         
|                                    |                                 | Sensing Systems, Ltd.                                   
|                                    | U.S. Traffic Corporation        |                                                         
|                                    |                                 | Quixote Transportation Safety Mexico S. de R.L. de C.V. 
|                                    | Energy Absorption Systems, Inc. |                                                         
|                                    |                                 | E-Tech Testing Services, Inc.                           
|                                    |                                 | Spin-Cast Plastics, Inc.                                
|                                    |                                 | Energy Absorption Systems (Europe), Inc.                
|                                    |                                 | Quixote Transportation Safety (Asia Pacific) Pty Limited
|                                    |                                 | Quixote Transportation Safety (Asia Pacific), Inc.      
|                                    |                                 | Quixote Transportation Safety (Europe), Inc.            
|                                    |                                 | Energy Absorption Systems (AL) LLC                      
|                                    | Peek Traffic Corporation        |                                                         
|Quixote Research Corporation*       |                                 | Delaware                                                
|Quixote Foreign Sales Corporation   |                                 | U.S. Virgin Islands                                     

Quixote
Transportation Safety, Inc., Quixote Research Corporation* and Quixote Foreign Sales Corporation are wholly-owned by Quixote Corporation.

TranSafe
Corporation, National Signal, Inc., Surface Systems, Inc., U.S. Traffic Corporation, Peek Traffic Corporation and Energy Absorption Systems, Inc. are
wholly-owned by Quixote Transportation Safety, Inc.

All
subsidiaries listed under TranSafe Corporation, Highway Information Systems, Inc., Surface Systems, Inc. and Energy Absorption Systems, Inc. are wholly-owned by
those corporations.

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